It is well known that the thermal efficiency of an internal combustion engine is very low. The energy not extracted as usable mechanical energy is typically expelled as waste heat into the atmosphere by way of the engine's exhaust gas emission, charge air cooling and engine coolant heat rejection.
It is known to employ a relatively simple, closed-loop Organic Rankine Cycle (ORC) system to recapture the engine's waste heat otherwise lost to the surrounding ambient. Such a system typically comprises a circulating pump, pumping a liquid phase organic, working fluid through a boiler wherein the working fluid undergoes a phase change from a liquid to a pressurized, gaseous phase. The boiler receives its heat input from the engine's waste heat streams. The gaseous phase working fluid expands through a turbine wherein mechanical work is extracted from the turbine. A low pressure vapor, typically exiting the turbine, then enters a condenser intended to cool and return the two phase fluid to a saturated liquid phase for recirculation by the circulating pump. A receiver is typically placed between the condenser and the recirculation pump to accumulate and separate the liquid portion of the fluid from any surviving gaseous phase exiting the condenser. The fluid passing through the condenser is typically cooled by a suitable cooling medium directed through the condenser. However, improvements are desirable.